Irrigation systems utilizing multiple sprinkle heads have been used to water large areas of..turf on lawns, parks, golf courses, and the like. These systems usually contain a large water pipe ("lateral") that is buried several feet below the ground surface and, as off-shoots from the lateral, smaller pipes ("risers") extending upward to where the sprinkle heads are located. The sprinkler heads of most modern systems are often mounted substantially even with the surface of the turf topsoil; and such sprinkler heads often have a "pop-up" feature.
Some pop-up sprinklers which have found wide commercial acceptance are described in U.S. Pat. Nos. 3,107,056, 3,261,553, and 3,713,584 of Hunter. An improved pop-up sprinkler structure is disclosed in U.S. Pat. No. 4,850,532 of Mackanos. The disclosure of each of these patents is hereby disclosed by reference into this specification.
In general, in the pop-up sprinkler structures, a flat disc covers the sprinkler nozzles and the rotational member to which the nozzles are mounted; thus, when the system is not in use, only the flat disc laying level with the ground is visible when the system is not in use.
When the pop-up nozzle is energized by water pressure, the plate and nozzles rise several inches above the ground surface; and, with the nozzles rotated around the sprinkler heads by an integral, water-driven hydraulic motor, large areas of turf can be evenly watered. When the water pressure is removed, the nozzles and the cover plate return downward.
Many of the pop-up sprinklers currently in use are connected to the risers by swing-joints. As is known to those skilled in the art, these joints are flexible, and they usually are comprised of a combination of piping elbows, nipples, and short lengths of pipe. With the use of such a joint, one may form a flexible riser to allow precise positioning of the sprinkler head in the ground surface. See, for example, an article entitled "Swing Joints--Vital Components of Valve-In-Head Irrigation Systems," appearing at pages 35 et seq. of the March, 1989 issue of "Sports Turf" magazine(Gold Trade Publishing Company, Van Nuys, Calif.), the disclosure of which is hereby incorporated by reference into this specification.
However, with some irrigation systems, the flexibility of the swing-joint system can cause problems. Thus, for example, with golf courses that are located in a sandy location (such as. e.g., in Florida), the turf laid over the sandy substrate must be irrigated regularly. Because both the sprinkler head and its attendant swing joint repose in sand, after a period of time the combination of the sprinkler head movement, the flexibility of the swing joint, and the plasticity of the water-soaked sand cause the sprinkler head to become buried in the sand. Once the occurs, the sprinkler system cannot function well.
It is an object of this invention to provide a process for raising and repositioning sunken sprinkler heads.
It is another object of this invention to provide an apparatus for raising and repositioning sunken sprinkler heads.